This update of an earlier work is entitled True or False Possession: How to Distinguish the Demonic From the Demented. The author, French neurologist Jean Lhermitte, originally wrote this book in the 1960s; this new edition has been edited and updated by Dr. Aaron Kheriaty, bestselling author of The Catholic Guide to Depression.

Written primarily for health professionals,True or False Possession is nonetheless of interest to any educated Catholic, in that it recounts from a Catholic viewpoint genuine suspected demonic possession and helps the layman, priest, psychiatrist and even family members to distinguish the real thing from mental illness and fakery. However, when and if it is necessary to bring the victim to an exorcist for treatment, Dr. Kheriaty points out, "This author knows the permanent limitations of his science: This book does not attempt to detail cases of what may be considered true possession, for these by their nature would be outside the scope of the author’s clinical expertise. In such cases, the physician and priest need to collaborate responsibly and with respect for the insights of both science and theology."

Not surprisingly, given the profession, the medical emphasis of the book is paramount, yet the author writes as a convinced Catholic and, as such, gives what is almost a short history of diabolical possession from the time of Christ’s exorcisms, as recorded in the Gospels, up to his own time. The author recounts examples of saints to whom the devil appeared, such as doctor of the Church St. Teresa of Avila: "She depicts the evil one as possessing hideous form, with a terrifying mouth and a regular proteus, able to transform and to multiply himself."

Nevertheless, while there are many spine-chilling accounts of true diabolical possession, in particular of well-known nuns who rose to be prioresses of their monasteries while under the control of Satan, I will spare you the gruesome details.

Many seeming cases of diabolical possession were in fact cases of simple insanity or mental illness, as Lhermitte explains. And many more were simply frauds that, in turn, caused mass hysteria in others who simply suffered from neurological illnesses that produce symptoms having nothing to do with the devil or hidden demons.

Somewhat disturbing is this quotation towards the end of the book: "In 1948, a celebrated demonologist under the aegis of London University revealed that, in all districts of London, there are hundreds of men and women of excellent education and intellect and high social position who worship the devil and offer him a regular cult." I shudder to think of what such a survey might reveal in our country.

Keep some holy water by your side as you read this book, and remember that Satan and his fallen angels are the biggest losers in the history of God’s creation. Though more powerful than we are in our natural state, we are under Divine protection, so simply scorn them, use all sacramental means possible to reject them, and through your friendships, bring your friends and family members to the Lord.